Improvement of oral lesions associated with malignant acanthosis nigricans after treatment of lung cancer.

A rare case of malignant acanthosis nigricans associated with lung cancer is presented. The case involved a 70-year-old man who had oral changes and various immunologic dysfunctions, including an increase in antinuclear antibodies. Oral lesions were characterized by papillary hyperplasia, formation of grooves, pigmentation of the upper lip and cheeks, and a loss of taste sensation. After the patient's lung cancer was treated with anticancer drugs, the histopathologic examination showed a marked improvement in oral lesions and significant normalization of immunologic abnormalities. The present case provides unique evidence that oral lesions associated with acanthosis nigricans have a significant correlation with lung cancer and high titers of antinuclear antibodies.